Question

Novocain, a local anesthetic, is the ammonium salt of procaine. (14.5)

1. Draw the condensed structural formula for the ammonium salt (procaine hydrochloride) formed when procaine reacts with $\mathrm{HCl}$. (Hint: The tertiary amine reacts with HCl.)
2. Why is procaine hydrochloride used rather than procaine?

Short answer

Part (a):

• The condensed structural formula for the ammonium salt (procaine hydrochloride) formed when procaine reacts with $HCl$is
  

Part (b):

• Procaine is less commonly used because it is less soluble in body fluids than procaine hydrochloride (novocaine).

Step-by-step solution

Part (a) Step 1: Given Information 

We need to find the condensed structural formula for the ammonium salt when procaine reacts with $HCl$.

• Novocain, a local anesthetic, is the ammonium salt of procaine
• The Structure of procaine is

Part(a) Step 2: Explanation 

Condensed structural formula for the ammonium salt (procaine hydrochloride) formed when procaine reacts with$HCl$

• When procaine reacts with $HCl$, an amine salt of procaine hydrochloride is formed.
• The structure of the amine salt of procaine hydrochloride is

Part (b) Step 3: Given Information 

Frequent use of procaine hydrochloride rather than procaine

• Procaine is a local anesthetic and falls into the amino acid group.
• Procaine hydrochloride, also known as novocaine, is formed when procaine reacts with $HCl$
• Procaine is less commonly used because it is less soluble in body fluids than procaine hydrochloride (novocaine).